Albert e



A. E. COY.

TELEPHONE RECEIVER APPLICATION mm mm. 20, 1920.

1,403,592, Patented Jan. 17, 1922.

. Q q lerzlf ay ALBERT F. GUY, OF CHICAGO, ILLINOIfS.

TELEPHONE RECEIVER.

1.,ellllhlill2.

Specification of Letters Patent.

Patented Jan. It'll, tilt/2t.

Application filed March" 20, 1920. Serial No. 367,559.

To all whom s'i' may concern:

lie it known that l, lrnnnnr E. Cor, a citizen. oil? the United States, residing at Chicago, in the county of Cook and State of lillinois, have invented certain new and use iul lmprovements in Telephone Receivers of which the following is a specification.

'lhis invention relates to improvements in c] )ho1u receivers, and has especial reference to receivers for portable use.

Use of the objects oi the invention is to provide a relatively small telephone receiver, especially adapter l to a sound amplifying; system to enable partially dear persons to hear more distinctly.

Another object is to provide a means for adjusting the device to vary the magnetic liar: whereby to modify the intensity of operation thcreot conformable with the strength of the battery used.

Another object is to provide an especial construction. whereby the magnetic structure may bodi y be moved away from the die phraiz'ni a means tor adjustment, and provision ct means, outside ot the casing to visually indicate the extent of adjustment.

Another object is to provide a circuit controlling switch to control the circuit and having an operating end or handle projecting throug'gh the circumferential wall oi the casing,

Other, further and more particular objects of the invention will become readily apparent to persons skilled in the art, from a consideration of the following description when taken in conjunction with the drawings, wherein Fig. 1 is a rear view of the receiver, substantially the actual size oi the instrument.

Fig. 2 is a side elevation of the same.

3 is an enlarged interior view of the instrument with the cover removed.

lligr. 4t is a section taken on line l-l of l ip l igr. 5 is l i r. 3.

l ig. (3 is an enlarged perspective view oft the screw tor retracting the magnet from the diaparagm.

in all the views the same reference charactors are employed to indicate similar parts.

10 is the body part of the casing having two internal diameters and made, preferably, cl insulating material such as hard rubber, or the like, screw threaded, as at 11, to r ive a cap or cover 12, the latter being a section taken on line 5-5 of perforated centrally, as at 13, lying between the cover 12 and the circumferential edge 14-. of the casing; is the diaphragm 15.

permanent magnet 16, of cruciform shape (having four forwardly bent arms 1? with poles l9), and made of the best material, is provided with tour arms 17, extend ing from the base 18 to a point near tlu diaphragm, in the largest part of the cas' in as at 19. The part 19 is bent away from tli elcctro-magnet 20, much as may be within the casing, so as to position the poles thcrco' f as far from the center of the diaphragm, as may be. Connected to the base portion 18 o the permanent magnet, is a soft iron core 21.,

inade'ot Swede iron, or the like, and which may be electrically welded to the base la The core 21 is perforated, as at and threaded to receive a screw 23. The screw is split, as at 23, so as to prevent the ma 5;- net from having any undue lateral move ment, The screw 23 provided with a reduced portion 24L which. passes through the casing to receive a handle Projecting! from the handle, or hub portion 25, is an arm 26, carrying on its outer end a ball 2?. Overlying the outer end oi the screw is a cap 28, of the same material of which the casing 10 is composed. The cap, and the hub 25, being fastened to the screw end 24:, by means of a set screw 29. Around the rear face of the instrument are a series of hemispherical depressions or indentations to receive the ball 27, when the latter rotated around the axis carrying the screw 23 there with to hold the arm in adjusted position. A stop 31 limits the movement oi the lever 26 to one revolution. When the arm of lever 26, is rotated anti-clockwise, as shown in Fig. 1, the electro-magnet, as a whole, is moved forwardly thereby in the case ll), so that poles 19 and 21 oi? the magnet are moved to an extent toward the diaphragnn 15. When the lever 26 has been moved clockwise until it is again brought into contact with the stop 31, the magnet system will have been moved back into the casing id, as

far as it may be, and the maximum space is then existent between the end of the poles 19 and 21 and the diaphragm. The object of this arrangement is to modify the efl'ect of the electro-magnet on the diaphragm.

Inside of the casing 10 is a switch, 82, providing a switch blade 33, pivoted to the easing, as at 34-, and having a handle 35 projecting through a slot in the casi wall.

The end 36 of the switch blade is adapted to make electrical connection with the stationary contact 37. One terminal of the winding of the electro-maggnet 20, is connected to the terminal of the instrument 58 by wire 89 while the terminal 40 is connected by wire 41, with the contact 37 of the switch. The other terminal of the coil 42 is connected tc the switch blade as at The service wires id and 45 are connected to the terminals 10 and 38, respectively, and are held in the cas ing by a cleat L6 secured in place by the screws e7.

When the end 36 of the blade 33 makes electrical connection with the contact 37, the circuit through the instrument is closed and the position oi the handle with respect to the casing, will clearly indicate this fact.

Having described my invention what T claim as new and desire to secure hy l ietters Patent is In a telephone receiver a round casing having a central perforation to receive a means to move the enclosed magnet and having a series of concentrically arranged spaced apart depressions in the back sur face of the casing; a magnet in the casing; a stem threaded into said magnet and extending through said perforation; a hub on the outer end of said stein; an arm extending therefrom; a ball on its terminal end to he in the respective depressions when the arm is rotated and a thumb cap overlying said huh and fixed thereto, whereby to rotate the atom for moving said ma gnet.

In. testimony whereof I hereunto subscribe my name.

ALB Eli-T E. GUY. 

